pcbc_enc.c
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/*
* Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "des_locl.h"
void DES_pcbc_encrypt(const unsigned char *input, unsigned char *output,
long length, DES_key_schedule *schedule,
DES_cblock *ivec, int enc)
{
register DES_LONG sin0, sin1, xor0, xor1, tout0, tout1;
DES_LONG tin[2];
const unsigned char *in;
unsigned char *out, *iv;
in = input;
out = output;
iv = &(*ivec)[0];
if (enc) {
c2l(iv, xor0);
c2l(iv, xor1);
for (; length > 0; length -= 8) {
if (length >= 8) {
c2l(in, sin0);
c2l(in, sin1);
} else
c2ln(in, sin0, sin1, length);
tin[0] = sin0 ^ xor0;
tin[1] = sin1 ^ xor1;
DES_encrypt1((DES_LONG *)tin, schedule, DES_ENCRYPT);
tout0 = tin[0];
tout1 = tin[1];
xor0 = sin0 ^ tout0;
xor1 = sin1 ^ tout1;
l2c(tout0, out);
l2c(tout1, out);
}
} else {
c2l(iv, xor0);
c2l(iv, xor1);
for (; length > 0; length -= 8) {
c2l(in, sin0);
c2l(in, sin1);
tin[0] = sin0;
tin[1] = sin1;
DES_encrypt1((DES_LONG *)tin, schedule, DES_DECRYPT);
tout0 = tin[0] ^ xor0;
tout1 = tin[1] ^ xor1;
if (length >= 8) {
l2c(tout0, out);
l2c(tout1, out);
} else
l2cn(tout0, tout1, out, length);
xor0 = tout0 ^ sin0;
xor1 = tout1 ^ sin1;
}
}
tin[0] = tin[1] = 0;
sin0 = sin1 = xor0 = xor1 = tout0 = tout1 = 0;
}